FIELD OF THE INVENTION
The present invention relates to textile machines. Particularly this invention relates to spinning preparatory machines. More particularly, this invention relates to stop motion device of a lap forming machine.
BACKGROUND OF THE INVENTION
Generally, the lap forming machines are used for the preparation of lap from plurality of slivers for subsequent feeding to the lap processing machine, comber is known in the existing art of textiles production. The slivers arranged in the creel are doubled and drafted as per requirement by the drafting system of the lap forming machine. Since it may be more critical to process more number of sliver in a single drafting system, essentially a plurality of independent drafting systems provided with dedicated individual creel are used. The drafted slivers delivered in the form of lap sheet are subsequently combined together and delivered to the calendering rollers wherein the laps are compacted and delivered to the lap head. In the lap head, the lap is wound on the lap spool which is being held between the lap discs and driven by the lap rollers driven by the drive system of the lap forming machine. '
In the known art, the slivers are fed from cans to each drafting system through creel arrangement. Number of doubling will vary according to the requirement, generally ranges between 18-28 doubling. The slivers are drafted and converted as thin layer fibre sheet and plurality of such thin sheets are combined together and delivered to the calender rollers. A table is provided to guide the fibre sheet from drafting system to calender rollers in a

smooth way. In the delivery portion of each drafting system, at least a pair of rollers are provided on the surface of table so called as "Table calender rollers" for calendering the fibre sheet delivered from the drafting zone. The table calender roller presses the plurality of fibre sheets to form as compact lap sheet.
The natural fibres such as cotton, wool and synthetic fibres such as polyester, viscose are used as raw material for the production of yarn. The natural fibres contains wax and oily substances on its surface and also having higher moisture absorbency. The synthetic fibres generates static energy during processing on the machines. These would create a tendency on the material to stick with the parts of the machine during processing and the fibres would lapping over the mnning parts such as drafting rollers and calender rollers. Also, damaged machine parts or improper handling of material would create choking of material in the running path and obstruct the material flow. This would affect the performance of the machines and output quality of material being processed. Such continuous lapping and choking of material over the rollers would lead to damage of machine parts. To prevent such damages, various sensing means are provided to detect such lapping and choking and to stop the machine.
In the existing lap forming machines, a limit switch is provided in the back portion of top table calender roller to detect the lapping of material on either top or bottom table calender rollers. This limit switch arrangement would stop the machines only in the situation like lapping of material over the top or bottom table calender rollers and it would not detect the choking of material. To detect such choking, a sensor is provided in the front portion of top table calender roller.

The existing system comprises two separate sensing means for detecting tlie lapping and choking which would raise complexity in sensing and cost involved is higher.
Therefore there exists a persistent need to develop a system that would eliminate the disadvantages described above and to provide a simple and effective stop motion arrangement in the lap forming machines.
SUMMARY OF THE INVENTION
In the lap forming machines, the top calender roller is mounted on a top support and is freely movable in upward and downward direction. During normal running, the fibre sheets are passed between top and bottom calender rollers and get compressed. Whenever lapping occurs either on top or bottom calender roller, the top calender moves upwards. In the existing machines, a limit switch provided at the back portion of top calender roller with a minimum clearance. The upward movement of top calender roller activates the limit switch and the machine would be stopped. To detect the choking of material, a sensor is provided in the front portion of calender roller. Whenever the choking occurred in the front portion, it disconnects the signal between the transmitter and receiver and machine would be stopped.
In accordance with the aspect of present invention, the stop motion device for a lap forming machine comprises a table and table calender roller arrangement, said table calender roller arrangement comprises a bottom calender roller mounted on a bottom support, a top calender roller mounted over the bottom calender roller and a sensor characterized in that, at least

one blocking element is provided to disconnect tine signal between transmitter and receiver of the sensor.
According to the present invention, a blocking element is mounted on the end bush of top calender roller. The blocking element has a strip and is located near the bottom portion of transmitter part of sensor. Whenever lapping occurs, the blocking element also moves upwards along with the top calender roller and disconnects the signal between transmitter and receiver of said sensor and the machine would be stopped. Thus the usage of limit switch is eliminated and the machine is stopped using a single stop motion device in case of lapping or choking.
The method of present invention can also be used in other spinning machines such as carding, combing, drawing and spinning and twisting machines wherever the sensors are used as stop motion device.
OBJECT OF THE INVENTION
It is thus the basic object of the present invention to provide a simple and effective stop motion device which avoids aforementioned disadvantages of stop motion arrangement in the existing lap forming machines.
Another object of the present invention is to provide a stop motion device that would eliminate requirement of limit switches in the existing lap forming machines.
These and other objects, features and advantages of the present invention will become more apparent from the ensuing detailed description of the

invention taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Example embodiments are illustrated by way of example and not limitation in the figures of the accompanying figures, in which like references indicate similar elements and in which:
Fig - 1 is the schematic illustration of the existing system of the lap forming machine.
Fig - 2 of the drawings illustrates an isometric view of stop motion arrangement in the existing lap forming machines.
Fig - 3 of the drawings illustrates the stop motion arrangement in the existing lap forming machines.
Fig - 4 of the drawings illustrates an isometric view of stop motion arrangement according to the present invention.
Fig - 5 of the drawings illustrates the blocking element of stop motion device according to the present invention.
DETAILED DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will be described with reference to the drawings.

Attention is first invited to accompanying Figure - 1 that illustrates the
existing system of lap forming machine showing the position of the creel
zone, drafting zone, calendering zone, lap rollers and lap wound on spool.
The creel zone in the existing system is on one side of the head and arranged
in two separate lanes (1, 1'). A set of sliver cans are arranged at each lane
of creel arrangement. Two separate drafting systems (2, 2') are arranged one
after the other at a selective spacing. The slivers from each lane (1, 1') are
fed to their respective drafting system (2, 2') through the various guide
means. The drafting system (2, 2') and a set of table calender rollers (3, 3')
are mounted on a table (11) and the table is connected with the main head
(5). The output fibre sheet (12) from drafting system (2, 2') is over lapped one
over other and compressed by the table calender rollers (3, 3') before
entering into the calender rollers (6). The output lap sheet from calender
rollers (6) is wourid on spool by means of lap rollers (7, 7') to form a lap j
package (8). |
1
i Fig - 2 and Fig - 3 of the drawings illustrates the stop motion arrangement in
the existing lap forming machines. The table calender roller arrangement
consists a top calender roller (13) and a bottom calender roller (14). The
bottom calender roller (14) is mounted on a bottom support (15). The bottom
support (15) has a provision such as top support (16) and the end portion of j
top calender roller (13) is mounted on the grooved portion of top support (16) j
through an end bush. Said top calender roller (13) is mounted as a freely |
movable part and is capable to move only in upward and downward direction. j
I
A limit switch (17) is mounted in the back portion of top calender roller (13) j
with a minimum clearance using a mounting plate (18). A sensor (19) is I
mounted on the front portion of top and bottom calender rollers. The |
transmitter (19a) of the sensor (19) is mounted over the bottom support (15) j
I I

of one end of the table calender rollers and the receiver (19b) is mounted on the other end of the table calender rollers. Whenever lapping occurs either on top or bottom table calender rollers, the top calender roller (13) moves upwards and activates the limit switch (17) and stops the machine. If the material choked in the front portion of table calender rollers, the signal between transmitter (19a) and receiver (19b) disturbed and the machine would be stopped.
Fig - 4 and Fig - 5 of the drawings illustrates the blocking element and stop motion arrangement according to the present invention. The present invention eliminates the usage of limit switch (17) by providing a blocking element (20) for detecting the lapping and stops the machine in a simple way. The blocking element (20) is mounted on the top calender roller zone. The Front portion (22) of said blocking element (20) has an extended strip (21). The back portion of the blocking element (20) has mounting holes and is mounted on the end bush (24) of top calender roller (13) using the bolts (23).
The blocking element (20) is so arranged in a position that the strip (21) is located below the transmitter (19a). When the fiber sheet (12) wrapped over either top or bottom calender rollers, the top calender roller (13) moves upwards. The blocking element (20) connected with the end bush (24) of top calender roller (13) also moves along with the roller. Due to the upward motion, the strip (21) also moves upward and comes to a position in between transmitter (19a) and receiver (19b) and disconnect the signal passing between transmitter and receiver of the sensor (19) and the machine stops immediately.
Advantageously, the blocking element (20) can be made up of either

conductive or non conductive material.
Advantageously, the sensor (19) can be any kind of sensors such as photo electric sensor, Infrared sensor, Proximity sensor and the signal may be in the form of either light or rays.
Advantageously, the present invention can also be used in spinning preparatory machines such as carding, combing, drawing, spinning and twisting machines.

WE CLAIM:
1. Stop motion device for a lap forming machine comprises a table (11) and table calender roller arrangement, said table calender roller arrangement comprises a bottom calender roller (14) mounted on a bottom support (15), a top calender roller (13) mounted over the bottom calender roller (14) and a sensor (19) characterized in tliat, at least one blocking element (20) is provided to disconnect the signal between transmitter (19a) and receiver (19b) ofthe sensor (19).
2. Stop motion device as claimed in claim 1, characterized in that, the front portion (22) of said blocking element (20) consists an extended strip (21).
3. Stop motion device as claimed in claim 1, characterized in that, said blocking element (20) is rigidly mounted on the end bush (24) provided at the end portion of top calender roller (13).
4. Stop motion device as claimed in claim 1, characterized in that, the strip (21) in the blocking element (20) is located below the transmitter (19a).
5. Stop motion device as claimed in claim 1, characterized in that, the sensor (19) is a non contact sensor such as photo electric sensor. Infrared sensor or Proximity sensor.
6. Stop motion device as claimed in claim 1, characterized in that, the
blocking element (20) is made up of either conductive or non conductive
material.

7. A method of working of stop motion device for a textile machine
characterized in that, when the fibre sheet (12) wrapped over either top or
bottom calender rollers, the top calender roller (13) moves upwards and the
blocking element (20) connected with the end bush (24) of top calender roller
also moves along with the roller (13), due to the upward motion, the strip (21)
also moves upward and comes to a position in between transmitter (19a) and
receiver (19b) and disconnect the signal passing between transmitter and
receiver of the sensor (19) and the machine stops immediately.
8. Stop motion device and method as claimed in claim 1 to 7, characterized in
that, the method and device can also be used in spinning machines such as
carding, combing, drawing, spinning and twisting machines.
9. Stop motion device for a lap forming machine substantially as herein
described with reference to the accompanying drawings.